# My First Function

This documentation will guide you through executing your first function on the Teaclave platform.

# Prerequisites

To run Teaclave, a hardware with Intel SGX support is needed. You can check with this list of supported hardware. Note that you sometimes need to configure BIOS to enable SGX. Additionally, you need to install driver and platform software to run SGX applications. Details can be found in Intel SGX Installation Guide.

If you don't have an SGX supported hardware at hand, Teaclave can also run in simulation mode. However some functions like remote attestation will be disabled in this mode. Please start from here if you plan to try in simulation mode.

# Clone and Build Teaclave

Clone the Teaclave repository:

$ git clone https://github.com/apache/incubator-teaclave.git

Since the building dependencies are a bit complicated, we suggest to build the Teaclave platform with our docker images. You can learn more details about the building environment from Dockerfile under the docker directory.

Build the Teaclave platform using docker:

$ cd incubator-teaclave
$ docker run --rm -v $(pwd):/teaclave -w /teaclave \
  -it teaclave/teaclave-build-ubuntu-1804-sgx-2.9.1:latest \
   bash -c ". /root/.cargo/env && \
     . /opt/sgxsdk/environment && \
     mkdir -p build && cd build && \
     cmake -DTEST_MODE=ON .. && \
     make"

# Setup Attestation Service

For simplicity, we use Intel Attestation Service (IAS) in this tutorial. To get started, you need to enroll in Intel SGX Attestation Service in Intel's attestation service portal by subscribing the attestation service for development (linkable is preferred). Then, you can find "SPID" and "Primary key" in the subscription details for later usage.

There is one more setup if you are using linkable attestation service subscription. Edit the /etc/aesmd.conf file and uncomment the default quoting type = epid_linkable line to enable linkable quotes for EPID-based attestation service (i.e., Intel Attestation Service). At last, the AESM service needs to be restarted by sudo systemctl restart aesmd.

# Launch Teaclave Services

Teaclave contains multiple services. To ease the deployment, you can use docker-compose to manage all services in a containerized environment.

Setup environment variables:

$ export AS_SPID="00000000000000000000000000000000"  # SPID from IAS subscription
$ export AS_KEY="00000000000000000000000000000000"   # Primary key/Secondary key from IAS subscription
$ export AS_ALGO="sgx_epid"                          # Attestation algorithm, sgx_epid for IAS
$ export AS_URL="https://api.trustedservices.intel.com:443"    # IAS URL

Launch all services with docker-compose:

$ (cd docker && docker-compose -f docker-compose-ubuntu-1804.yml up --build)
Starting teaclave-authentication-service ... done
Starting teaclave-access-control-service ... done
Starting teaclave-scheduler-service      ... done
Starting teaclave-management-service     ... done
Starting teaclave-execution-service      ... done
Starting teaclave-frontend-service       ... done
Attaching to ...

# Invoke Function

We provide several examples to demonstrate the platform. Let's get started with invoking a built-in function: echo, which is a simple function that takes one input message and returns it.

This example is written in Python, and some dependencies are needed for the remote attestation. They can be installed with pip:

$ pip3 install pyopenssl toml cryptography

# Built-in function

Then, run the echo example:

$ cd examples/python
$ PYTHONPATH=../../sdk/python python3 builtin_echo.py 'Hello, Teaclave!'
[+] registering user
[+] login
[+] registering function
[+] creating task
[+] approving task
[+] invoking task
[+] getting result
[+] done
[+] function return:  b'Hello, Teaclave!'

If you see above log, this means that the function is successfully invoked in Teaclave.

# Define my own function

The previous example is to demonstrate invoking the built-in echo function. In Teaclave, you can also register and invoke a function written by yourself. For example, we can implement an echo function in Python like this:

$ cat mesapy_echo_payload.py
def entrypoint(argv):
    assert argv[0] == 'message'
    assert argv[1] is not None
    return argv[1]

Then run the mesapy echo example:

$ PYTHONPATH=../../sdk/python python3 mesapy_echo.py mesapy_echo_payload.py 'Hello, Teaclave!'
[+] registering user
[+] login
[+] registering function
[+] creating task
[+] approving task
[+] invoking task
[+] getting result
[+] done
[+] function return:  b'Hello, Teaclave!'

# Simulation Mode

To try Teaclave in SGX simulation mode, please install Intel SGX SDK first with instructions in Intel SGX Installation Guide.

Then clone and build Teaclave (with the -DSGX_SIM_MODE=ON option in cmake).

$ git clone https://github.com/apache/incubator-teaclave.git
$ cd incubator-teaclave
$ docker run --rm -v $(pwd):/teaclave -w /teaclave \
  -it teaclave/teaclave-build-ubuntu-1804-sgx-2.9.1:latest \
   bash -c ". /root/.cargo/env && \
     . /opt/sgxsdk/environment && \
     mkdir -p build && cd build && \
     cmake -DTEST_MODE=ON -DSGX_SIM_MODE=ON .. && \
     make"

Since the attestation is disabled in the simulation mode, related environment variables can be set to any values.

$ export AS_SPID="00000000000000000000000000000000"
$ export AS_KEY="00000000000000000000000000000000"
$ export AS_ALGO="sgx_epid"
$ export AS_URL="https://api.trustedservices.intel.com:443"

Under the simulation mode, you also need to change the docker-compose-ubuntu-1804.yml file accordingly to remove useless device/volume mappings which may not exist. That is, comment out these lines for all services in the docker-compose config file:

#      - type: bind
#        source: /var/run/aesmd/aesm.socket
#        target: /var/run/aesmd/aesm.socket
#    devices:
#      - /dev/isgx

At last, launch all services with docker-compose:

$ (cd docker && docker-compose -f docker-compose-ubuntu-1804.yml up --build)

In simulation mode, run examples with SGX_MODE=SW environment variable.

$ cd examples/python
$ SGX_MODE=SW PYTHONPATH=../../sdk/python python3 builtin_echo.py 'Hello, Teaclave!'
Last Updated: 6/19/2020, 3:13:12 PM